KR800001640B1 - Process for preparing coke of high quality - Google Patents

Abstract

This invention relates to the process for manufacturing coke of high quality. The coal used in this invention is liquefied with heavy ail to carbonize and coke. The heavy oil and the coal of 0.3-2 times weight of the heavy oil are heated to 300-4500C. After melting and scattering, the liquid is heated again to 5000C for carbonizing and coking.

Description

Manufacturing method of high quality coke

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing high quality coke, which can use not only high quality coal but also low quality coal such as weak coking coal and non-coking coal as a raw material.

In detail, the present invention relates to a method for producing high quality coke suitable for steelmaking and others by liquefying the coal with petroleum heavy oil and carbonizing and coking the liquefied water.

The coke is roughly divided into two types depending on the raw material. That is, coal coke manufactured using coal as a raw material, and petroleum coke or pitch coke made from petroleum heavy oil or coal tar as a raw material. And it is known that there exists a big difference between these coal coke, petroleum coke, or pitch coke in a manufacturing method, a property shape, and a use.

Among the coal coke, high quality coke obtained from strong coal briquettes is used entirely as steel coke.

However, in recent years, due to the lack of coking coal as a raw material, it has been attempted to manufacture steel coke from low quality coal such as weak coking coal and non-coking coal, which are themselves inadequate for producing high quality coke. The stage of commercialization has been reached.

The raw coal used at this time is what is called artificial coking coal or a coal briquette, and it is necessary to mix | blend coking coal with a raw material to some extent, and it was impossible to obtain high quality coke using only low quality coal like lignite coal.

Moreover, coal coke which uses coal as a raw material contains the ash content of several% to several 10% normally.

On the other hand, coke made from petroleum or coal-based heavy oil has little ash content and is usually 1% or less.

As a method for producing low ash coke containing coal, a coal-based heavy oil such as anthracene oil and coal are mixed and heat treated at about 350 ° C., and then solids are removed as a raw material. The method of sintering and what is called a swelling coal method are known.

The coke obtained in this way is used as a raw material for aluminum refinery electrode manufacture.

However, petroleum coke has the advantage of low ash content, high heat dissipation, high graphitization, and low electrical resistance when used in artificial graphite electrodes. . On the other hand, pitch coke is superior to petroleum coke in terms of high coke yield and thick meat, but is far from graphitizable.

The present inventors have conducted extensive research to develop a method for producing high-quality coke that can be used sufficiently as steel coke in low-quality coal such as weak coking coal and non-coking coal. As a result, a relatively large amount of petroleum heavy oil is applied to coal. The present invention finds that high-quality coke can be obtained by heat-treating at 300 to 450 ° C., dissolving at least a part thereof, and once making a pitch-like substance, then heating to a high temperature, carbonizing, and coking. Was achieved.

That is, the present invention has a coal of 0.3 to 2 times the weight of petroleum-based heavy oil or heat-treated petroleum-based heavy oil, and heat-treated until 300 to 450 ° C until a uniform dispersion state is obtained, and then 500 ° C or more. It is to provide a method for producing a high quality coke characterized in that the carbonization and coke to be heated by heating to.

It is a first object of the present invention to provide a process for producing high quality coke using coal.

A second object of the present invention is to provide a method for producing high quality coke using only low quality coals such as weak coal briquettes and low coking coal.

A third object of the present invention is to provide a method for producing high quality coke with low ash content.

It is a fourth object of the present invention to provide a method for producing high quality coke, in which a carbon molded product can also be obtained as a by-product.

Other objects, features and advantages of the present invention will become apparent from the following description.

In one embodiment of the present invention, 0.3-2 times the weight of coal is added to petroleum-based heavy oil or heat-treated petroleum-based heavy oil until it is heated until a uniform dispersed state is obtained at 300 to 450 캜.

As petroleum heavy oil used as a raw material in this invention, straight asphalt, stripping asphalt, etc. are mentioned.

These can be used by heating to 400-450 degreeC in advance as desired.

Moreover, as coal mixed with this petroleum heavy oil, not only high quality coals, such as anthracite coal, coking coal, and coking coal, but also low quality coals, such as weak coking coal, non-coking coal, lignite coal, are mentioned.

This coal is mixed with heavy oil in the ratio of 0.3-2 times weight as mentioned above.

If the amount of this coal exceeds this range, sufficient heat dissipation will not be achieved in heat processing, and it will become impossible to fully utilize the advantages of the petroleum coke obtained from petroleum heavy oil.

At 0.3 times or less by weight, the yield of coke is lowered and the meat quality of coke is insufficient, so that coke with high strength cannot be obtained. Speaking of petroleum heavy oil, it is not used as a binder between coal particles but is added to dissolve and liquefy coal by heat treatment. Therefore, the amount in the above range is required as a sufficient amount.

At this time, when petroleum heavy oil is used as it is, the amount of coal to be mixed is preferably 0.3 to 1 times the weight. However, when using petroleum heavy oil which has been heat treated at 400 to 450 ° C. and pitched in advance, coal is used. It is preferable to make the amount of 0.3 to 2 times the weight.

Heat treatment of the mixture of petroleum heavy oil and coal needs to be performed at 300-450 degreeC for at least 30 minutes.

At this time, especially when heavy oil is used without heat treatment, heating with sufficient stirring is advantageous.

It is necessary to change the temperature and time of this heat processing according to the kind of heavy oil within the said range.

That is, when using straight asphalt or peeled asphalt as it is, the temperature range of 400-450 degreeC is preferable.

In this case, since about 50% of the asphalt is discharged out of the structure as decomposition oil, the amount of coal added is preferably about 0.3 to 1 times the weight as described above.

On the other hand, when using the asphalt pitched by heat processing beforehand, the temperature range of 300-450 degreeC is preferable.

By this heat treatment, a part of the coal is dissolved in heavy oil, and the undissolved coal is uniformly dispersed therein. For example, most of cohesive coal such as mielite coal is dissolved, but only about 50% is dissolved in non-coking coal such as Pacific coal.

In the latter case, undissolved coal is in a state dispersed in heavy oil. These heat treatments are performed until the coal component is uniformly dissolved or dispersed in heavy oil, but this usually requires a treatment time of at least 30 minutes. Even when either asphalt or pitched asphalt is used, generation of optically anisotropic portions around undissolved coal can be recognized.

Since this optically anisotropic portion is known to be produced in heavy oil, the presence of coal in the vicinity of coal indicates that the coal can be uniformly and easily dispersed in the heavy oil and that no separation occurs.

The carbonization and coking in the method of the present invention are performed by stirring the mixture of the heavy oil and coal which have been heat-treated as described above as it is, or by stopping the stirring and raising the temperature to 500 ° C or more again.

When the heat treatment is performed until the whole is carbonized and solidified while stirring, the carbide obtained exhibits needle shape in appearance.

In the absence of agitation, the appearance is different depending on whether the asphalt fraction is used as it is, or if the fraction is subjected to a heat treatment in advance.

In the former case, it is usually an aggregate of spheres having a diameter of 2 to 3 mm called a caviar, but in the latter case, it is closer to a needle bed. In addition, when lignite is used as coal, in the heat treatment process with heavy oil, it becomes fine with stirring, and coal particles are hardly seen in the coke obtained, and fine pores exist in the whole surface.

The carbide obtained as described above is calcined again at 1,000 ° C. or higher to obtain coke.

The coke obtained all have high strength.

In another embodiment of the present invention, the mixture of the heat-treated heavy oil and coal may be carbonized and coked after removing the solids in the mixture instead of being carbonized and coked.

In this embodiment, the removal of this solid content is accomplished by dissolving using a suitable solvent such as quinoline, atracene oil and the like and removing the insoluble content by filtration or centrifugation.

What removed solid content is pitch shape or this as it is heated up at temperature higher than 450 degreeC, and carbonizes and cokes as mentioned above. The coke obtained in this case is 1% by weight or less of ash, and thick meat is obtained with good yield.

In addition, carbonization and coking may be performed normally using a silo type or the delayed coking method.

In the present invention, the above-mentioned solids are generally separated using a centrifugal separation method, a cyclone method, a solvent extraction method, a filtration method, or a precipitation method for lowering the viscosity by a suitable method.

Since the obtained solid substance is a fine powder, it shape | molds by the shaping | molding method put into a mold. The molding pressure is up to 2,000 kg / cm 2.

The molded body is calcined and carbonized to about 1,000 ° C. in a non-oxidizing atmosphere according to a conventional method.

The maximum of this firing temperature is due to the melting point of the ash contained in a large amount in the solid material.

When a large amount of alkali metal is contained in the ash, the ash is melted at about 1,200 ° C.

When the ash is melted, the molded body is destroyed.

The carbon molded product thus obtained is compact and has high strength. Therefore, it can be used as a structural member which is heat resistant, such as a carbon block. This solid can be molded without using a binder, and a very dense carbon material can be obtained.

That is, when coal is added to heavy oil and heat-treated to a temperature range of 300-450 degreeC, coal will melt | dissolve by heat and heavy oil.

The amount of dissolution varies depending on the type of coal, but generally decreases as the degree of coalification from bituminous coal to lignite decreases. In other words, undissolved coal exists, but mesophase generated in heavy oil exists around the coal particles.

In short, the coal particles were found to be wrapped in mesophase. The coal particles wrapped in this mesophase are solid and can be completely separated from the liquid phase.

The separated solid is rounded as a whole, and it can be seen that the surface has irregularities.

In other words, the size of the mesophase on the surface of coal is smaller than that of coal particles, and is about 3 μm in spherical shape, which adheres to the surface of coal particles and coalesces spheres.

In other words, when the mesophase separates the solids from the liquid phase, the mesophase is firmly attached or fused to the surface of the coal particles, so that the coal particles and the mesophase do not fall.

As mentioned above, the surface of the separated solid has mesophase. Therefore, as mentioned above, by using both the pitch and carbon properties of the mesophase, the solid is press-molded and fired as it is without using a binder, thereby obtaining a very compact and high-strength carbon molded body. Next, although an Example demonstrates this invention again, the scope of the present invention is not limited by this.

Example 1

With respect to 1 weight part of coal pulverized by 60-100 mesh, it had 2 weight part of vacuum distillation sedimentation oils of the gyp supporting oil, heated to 420 degreeC under normal pressure, stirring, and hold | maintained at this temperature for 60 minutes.

The cracked oil produced by this treatment was collected in a trap and 52.4% by weight of a pitch substance was obtained as the rest.

300 g of this pitch was put into the stainless container of 156 mm of inside diameters and 300 mm of depth, and it heated at 420 degreeC for 20 hours, and then at 500 degreeC for 1 hour, and obtained 225 g of carbides.

The carbide was then heated to 1,350 ° C. for 30 minutes to obtain 210 g of coke.

Appearance of this coke is a collection of spherical bodies having a diameter of about 3 mm, the physical properties of which are shown in the first table.

In addition, in the observation of the coke's polarization microscope, the coke's structure is thought to be coal particles in the center of the spherical body constituting the coke, and the surroundings contain carbon crystals of fine mosaic structure. It was recognized.

Next, with respect to adding 1 part by weight of precipitated oil to 1 part by weight of coal, the yield of coke when treated as described above was 73% by weight relative to the raw material.

The appearance was almost the same as the above coke, and the physical properties were as shown in the first table.

[Table 1]

Example 2

2 parts by weight of vacuum distilled precipitated oil obtained from katasapran crude oil were added to 1 part by weight of myelite pulverized with 60 to 100 mesh, heated to 400 ° C. under normal pressure while stirring, and treated at this temperature for 30 minutes. It was. Then, stirring was stopped, it was raised to 450 degreeC, it hold | maintained at this temperature for 20 hours, and also processed at 500 degreeC for 1 hour.

The obtained carbide was calcined at 1,350 ° C. for 30 minutes to obtain coke.

The yield of coke was 51.6 weight% with respect to the raw material.

The appearance of this coke was almost the same as that of Example 1, but the structure of the coke was about 10 to 30 µm in size, unlike that of Example 1, and the size of the coal particles used was the same. It was recognized that it was smaller by about one tenth of one.

The physical properties of the coke are as shown in the second table.

The amount of precipitated oil is 1 part by weight with respect to 1 part by weight of coal, and the yield of coke obtained by treatment as described above is 53.6% by weight with respect to the raw material, and the physical properties thereof are as shown in the second table.

[Table 2]

Example 3

1 part by weight of sediment oil from the gap support oil was added to 1 part by weight of coal moeltan, Australian coal and lignite pulverized to 60 to 100 mesh, and heated at 420 ° C. for 60 minutes while stirring.

The yield of the obtained pitch was 60.3 wt%.

This pitch was processed in 500 degreeC for 1 hour like Example 1, and carbide was obtained.

This was baked to 1,350 degreeC again and the coke was obtained.

The yield of coke was 41.3% by weight based on the raw materials.

The appearance of this coke is that the pores of Examples 1 and 2 were aggregates of spherical bodies, and the fine pores were substantially uniform, and the structure was refined and uniformly so that the coal particles were difficult to see under the microscope. It was distributed.

Moreover, 1 weight part of this pitch was added with respect to 1 weight part of coal, and it heat-processed at 400 degreeC for 60 minutes, stirring, using the pitch obtained by heat-processing the sedimented oil in the gab support oil at normal pressure and 420 degreeC.

Subsequently, heat treatment was performed at 450 degreeC for 20 hours, and also at 500 degreeC for 1 hour, and carbide was obtained.

This carbide was calcined at 1,350 ° C to obtain coke.

The yield of coke was about 68.6% by weight of the raw material.

The appearance of this coke was largely the same as the above, but the pores were smaller and harder.

The physical properties of these cokes are shown in Table 3.

[Table 3]

Example 4

The precipitated oil obtained from the gap supporting oil was heat-treated at 400 ° C. for 60 minutes under normal pressure.

58.3 weight% of pitch was obtained as what was left to a bowl.

In correspondence with 1 part by weight of the pitch, 2 parts by weight of the myelite pulverized into 60 to 100 mesh was added, followed by heat treatment at 320 ° C. for 60 minutes while stirring. What was obtained was in pitch shape, and the yield was 92.5 weight%.

The structure of this pitch thing was not recognizable by coal particles at all.

This was put into the container similar to Example 1, and it processed at 420 degreeC for 20 hours, and then at 500 degreeC for 1 hour.

The yield of the obtained carbide was 78.4 wt% with respect to the pitch material. This carbide was calcined again to 1,350 ° C to obtain coke. The yield of coke was 65.2% by weight relative to the pitch material. The appearance of this coke had a structure closer to acicular shape than that of Example 2, and the structure by a polarizing microscope had a very fine optically anisotropic structure.

Moreover, 1 weight part of coals were added with respect to 1 weight part of pitches obtained as mentioned above, and it heat-processed at 380 degreeC for 1 hour, stirring.

The obtained pitch substance was 92.1 weight%.

This pitch-like substance was coked as mentioned above.

The yield of coke was 63.8% by weight relative to the pitch material. The appearance and the structure of this coke were almost the same as the above. The physical properties of the obtained coke are shown in Table 4.

[Table 4]

Example 5

The precipitated oil obtained from the gap support oil was heat-treated at 420 ° C. for 60 minutes while stirring at atmospheric pressure.

52.6 weight% of pitch was obtained as what was left to a bowl.

2 parts by weight of coal pulverized to 60 to 100 mesh was added to 1 part by weight of the pitch, and heat-treated at 400 ° C. for 60 minutes.

What was obtained was a pitch substance, and the yield was 87.4 weight%.

This pitch-like substance was carbonized by heating to 500 ° C as in Example 1.

The yield of this carbide was 81.0 wt% based on the pitch material.

This was baked to 1,350 degreeC again and the coke was obtained.

The yield of coke was 69.7% by weight based on the pitch material.

This coke had a different appearance from that obtained in Example 1 and was close to a bed.

Moreover, 2 weight part of coals were added with respect to 1 weight part of pitches mentioned above, and the coke obtained by the above operation was almost the same as the above, and the yield was 71.8 weight% with respect to a pitch substance. The physical properties of these kocos are shown in Table 5.

[Table 5]

Example 6

Asphalt fractionation obtained as a vacuum distillation precipitate of the gap support oil was heat-treated at 420 ° C. for 60 minutes in advance to obtain a pitch.

2 parts by weight of microelite (three ashes, ash content 7.4%) was added to 1 part by weight of the pitch, and the resultant was heat-treated at 400 ° C. for 60 minutes.

The yield of the obtained pitch substance was 93.4 weight% with respect to the raw material. Three times amount of quinoline was added to this pitch substance, and it heated at 90 degreeC, and dissolved.

Subsequently, the solids were separated by centrifugal precipitation, and the soluble component was removed from quinoline by distillation under reduced pressure to obtain quinoline-soluble pitch substance.

This yield was 89.8 weight% with respect to a pitch substance, and ash content was 0.07 weight%.

The quinoline soluble pitch-like substance was put into a cylindrical stainless container having an inner diameter of 150 mm and a length of 300 mm, and carbonized by heat treatment at 450 ° C. for 24 hours and then at 500 ° C. for 1 hour.

The yield of this carbide was 65.3%.

This carbide was further calcined to 1,350 ° C to obtain coke.

The yield of coke was 52.6% by weight.

The physical properties of this are shown in the first table.

Further, 2 parts by weight of unepitane was added to 1 part by weight of the pitch described above, followed by heat treatment at 340 ° C. for 60 minutes to obtain 95.3% of a pitch substance.

This pitch-like material was treated as above to produce coke. The yield of the obtained coke was 55.9 weight% with respect to the pitch-like substance for quinolines.

In all the external appearances of the obtained coke, the flesh was thick and the shape was close to the bed.

The physical properties of this are shown in Table 6.

[Table 6]

Example 7

To 2 parts by weight of the asphalt fraction obtained as depressurized precipitated oil of the garp support oil, 1 part by weight of migraine coal pulverized with 60 to 100 mesh was added and heat-treated at 430 ° C. for 60 minutes.

The yield of the obtained pitch substance was 43.8 weight% with respect to the raw material.

The anthracene oil was added 3 times with respect to this pitch-like substance, and solid content was removed as the insoluble content.

The anthracene oil soluble fraction removed anthracene oil by distillation and obtained the pitch substance.

Its yield was 78.3% by weight based on the pitch material.

The coke was carried out in the same manner as in Example 6.

The obtained coke had a slightly thinner meat than that of Example 1, but was closer to the needle bed.

The physical properties of this coke are shown in Table 7.

[Table 7]

Example 8

1 part by weight of pacific coal was added to 1 part by weight of the pitch-precipitated oil of the support gas obtained at 420 ° C. for 60 minutes in advance, and heat-treated at 400 ° C. for 60 minutes.

The obtained pitch substance was 87.4 weight% with respect to the raw material.

Three times amount of quinoline was added to this pitch substance to separate solids, and quinoline was removed to obtain quinoline-soluble pitch substance.

Its yield was 70.4% by weight and the ash content was 0.56% by weight.

This was coked by the same operation as in Example 1.

The yield of coke was 62.4% by weight relative to the pitch material.

This coke was substantially the same as Example 7 in appearance.

The physical properties are shown in Table 8.

[Table 8]

Example 9

1 part of coal (three ashes, 7.4% of ash content) pulverized with 60-100 mesh was added to 2 parts of vacuum distillation sedimentation oils of the support gas, and heat-processed at 420 degreeC for 60 minutes.

The obtained pitch substance is 71.2% with respect to a raw material.

Three times amount of quinoline was added to 1 part of this pitch-like substance, and it was made to melt-dissolve at 90 degreeC for 1 hour.

This was subjected to a centrifugal precipitator, and after removing the floated product, benzene was added to the precipitate, followed by filtration to separate 25.6% of the solids from the pitch-like substance as quinoline insolubles.

After drying this solid, it shape | molded at normal temperature under the pressure of 2000 kg / cm <2> by the shaping | molding machine.

The molded body was put in coke, heated to 1000 degreeC at the temperature increase rate of 40 degreeC / hr of mesh, and it hold | maintained at this temperature for 1 hour.

The obtained carbon molded product was very hard.

The physical properties are shown in Table 9.

In addition, when describing the structure of the pitch-like substance, it can be seen that the coal particles are rounded and surrounded by mesophases appearing white.

Moreover, it heat-processed for 60 minutes at 410 degreeC using the above raw materials. The yield of the obtained pitch substance was 80.3% with respect to the raw material, and the amount of solids as quinoline insoluble was 17.2% with respect to the pitch substance.

The solids had an average size of 80 µm and a ash content of 17.0%.

This solid material was molded and carbonized in the same manner as in Example 1 to obtain a carbon molded product.

The physical properties of the obtained carbon molded product are shown in Table 9.

Further, as described above, heat treatment at 450 ° C. for 60 minutes yields a pitch substance at a yield of 60.8%.

Its amount of solid as a quinoline insoluble was 69% with respect to the pitch material.

This partly became a large mass, which was pulverized to 100 mesh or less, formed and carbonized as described above to obtain a carbon molded body.

The physical properties of the obtained carbon molded product are shown in Table 9.

[Table 9]

Example 10

To 1 part of the pitch obtained by heat-treating the pressure-retained precipitated oil of the support gas at 420 ° C. for 60 minutes in advance, 1 part of the finely crushed powder of 60-100 mesh was added and heat-treated at 400 ° C. for 60 minutes.

The yield of the obtained pitch substance was 92% with respect to the raw material. This was dissolved in quinoline and decomposed to separate solids.

The yield of this solid was 10.2% with respect to the pitch substance, and the ash content was 45.2%.

This solid material was molded and carbonized in the same manner as in Example 9 to obtain a carbon molded product.

Table 10 shows the physical properties of the obtained carbon molded product.

Moreover, using the raw materials as mentioned above, 2 parts of unemitted coal was added with respect to 1 part of pitches, and it heat-processed at 360 degreeC for 1 hour. The yield of the obtained pitch substance was 94.3% with respect to the raw material. In this pitch material, quinoline was used to separate the solids.

The yield of the obtained solid was 19.7% with respect to the pitch substance, and the ash content was 20.1%.

This was molded and carbonized in the same manner as in Example 9 to obtain a carbon molded product. Table 10 shows the physical properties of the obtained carbon molded product.

[Table 10]

Example 11

To 2 parts of pitch obtained by heat-preparing the reduced pressure precipitated oil of the support gas at 420 ° C for 30 minutes in advance, add 1 part of pacific coal (18.7% ash content) pulverized to 60 to 100 mesh, and then to 60 ° C at 400 ° C. Heat treatment was performed for a minute. The yield of the obtained pitch substance was 89% with respect to the raw material.

Anthracene oil was added to this pitch substance three times, and it heated at 90 degreeC, melt | dissolved, and obtained the solid substance as the insoluble content.

The yield of this solid was 30.3% based on the pitch material, and the ash content was 21.6%.

This solid material was molded and carbonized in the same manner as in Example 11 to obtain a carbon molded product.

The physical properties of the obtained carbon molded product were solid with a specific gravity of 1.62 (g / cc), a true specific gravity of 2.01, and a compressive strength of 3.130 (kg / cm 2).

Claims (1)

0.3-2 times the weight of coal is added to petroleum-based heavy oil or heat-treated petroleum-based heavy oil, and heated, dissolved and dispersed at 300-450 ° C, and then heated to 500 ° C or higher, or heated and dispersed to obtain solids. A method for producing a high quality coke, characterized by heating at 500 ° C. or more, carbonizing and coking.